I'll have to look up Planetary Annihilation. You make it look boss!
The robots torso looks like it could be connected to the lower half by three points, making the middle look sleek with support hydraulics on ether side. It would need to be lit up a bit behind him to confirm this. An example of a robot with a complexly connected torso would be The Fallen from Transformers 2 Revenge of the Fallen.